Biomedical subjects

S Contractor

Publications and source records attributed to S Contractor.

5 recordsLinked to original sources

PubMed2000

Does a herniated nucleus pulposus contribute significantly to a decrease in height of the intervertebral disc? Quantitative volumetric MRI.

A lumbar intervertebral disc with a herniated nucleus pulposus (HNP) often exhibits a decrease in the height of the intervertebral space. Our purpose was to ascertain whether the loss of volume of an HNP is sufficient to cause a perceptible decrease in the height of the intervertebral space. MRI of 44 patients with 51 HNPs were reviewed. The volumes of the herniated material and of the intervertebral discs were calculated for every level from L1-2 to L5-S1. The average volume of the HNP was 503 +/- 301 mm3. The average volumes of all 220 intervertebral discs and of the 127 normal-appearing discs were 14,442 +/- 4200 mm3 and 17,476 +/- 2885 mm3 respectively. The average volume of the HNP represented 3.5% of the parent disc. An average HNP caused a decrease in intervertebral space height of 0.35 mm (0.56 pixels). Therefore, the loss of the volume of the HNP does not cause a significant decrease in the intervertebral space height. The average calculated decrease in the disc height is less than that reported in normal diurnal variation.

Adult↗

PubMed2000

Transient mediastinal enlargement: an unusual computed tomographic manifestation of pulmonary venous hypertension and congestive heart failure.

We describe a case of diffuse superior and middle mediastinal enlargement of soft tissue attenuation noted on helical computed tomography (CT) of a patient with clinical and radiographic findings of congestive heart failure (CHF). Upon treatment and improvement of his pulmonary venous hypertension, a repeat CT scan revealed resolution of the mediastinal abnormalities. We, therefore, advocate a search for primary CT signs of CHF in patients with findings of widespread mediastinal distension. If present, repeat CT scanning after resolution of the cardiac condition should be performed before further intervention for the mediastinal abnormality is attempted.

Heart Failure↗

PubMed1999

Optimization of gray/white matter contrast with fast inversion recovery for myelin suppression: a comparison of fast spin-echo and echo-planar MR imaging sequences.

We compared two MR imaging sequences, fast inversion recovery for myelin suppression (FIRMS) and echo-planar FIRMS (EP-FIRMS), for depicting gray/white matter contrast. In 18 patients, the frequency bandwidth (BW) was optimized for each sequence; in nine patients, the BW was held constant. In the BW-optimized group, the mean contrast-to-noise ratio (C/N) was three times higher with the FIRMS sequence. In the BW-constant group, the mean C/N was 27% higher with the EP-FIRMS sequence; however, geometric distortion degraded the EP-FIRMS images excessively. For optimal gray/white contrast, FIRMS appears to be the superior pulse sequence.

Brain Diseases↗

PubMed1985

Iodinated fibroblast beta-glucuronidase as a ligand for receptor-mediated endocytosis.

Antibodies raised to human placental beta-glucuronidase were shown to cross-react with the beta-glucuronidase secreted by mouse 3T3 fibroblasts, but did not react with other lysosomal enzymes. The beta-glucuronidase secreted by 3T3 cells was purified 15000-fold by chromatography on an affinity column made from this antibody and resolved into a single component, of Mr 68000, by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Iodinated samples of purified enzyme were taken up into mouse peritoneal macrophages by receptor-mediated endocytosis at a rate similar to that calculated previously for unlabelled enzyme, and uptake was competitively inhibited by yeast mannan. Binding of beta-glucuronidase to macrophages was saturable, with a Kd of 7 X 10(-9)l/mol, an affinity comparable with that calculated for the binding of mannosylated bovine serum albumin (Kd 1.3 X 10(-9)l/mol), a ligand specific for mannose receptors. Four times as many molecules of mannosylated albumin (12000) as of beta-glucuronidase (3000), however, bound to each cell. This purification and iodination procedure did not therefore have any adverse effect on the uptake properties of secreted beta-glucuronidase, and provides a ligand with which to investigate binding and specific endocytosis into a range of different types of cell.

Animals↗

PubMedDate not supplied

Neonatal thrombosis with anticardiolipin antibody in baby and mother.

The anticardiolipin antibody is associated with increased risk of thrombosis, which is manifested with various clinical presentations, including vascular thrombosis, recurrent fetal wastage, and neurologic defects. We report a case of neonatal thrombosis occurring in the renal vein and inferior vena cava associated with moderate positive anticardiolipin antibody titer in the baby while the maternal serum showed even stronger anticardiolipin antibody of immunoglobulin G class. Subsequent follow-up over the 4 months postpartum period showed a disappearance of the antibody in the baby, whereas the mother's antibody persisted. This case illustrates the fact that the maternal anticardiolipin antibody can be transferred to the fetus and may be a risk factor for thrombosis in the neonates. Anticardiolipin antibody syndrome should be considered in the differential diagnosis of neonatal thrombosis.

Adult↗